Similar to the electron transport chain, the light-dependent reactions of photosynthesis pump protons into the thylakoid lumen of chloroplasts to drive the synthesis of ATP by ATP synthase. The proton gradient can be generated through either noncyclic or cyclic photophosphorylation. Of the proteins that participate in noncyclic photophosphorylation, photosystem II (PSII), plastiquinone, and cytochrome b f complex directly contribute to generating the proton gradient. For each four photons absorbed by PSII, eight protons are pumped into the lumen. The total equation for photophosphorylation is shown:

Answer this question: where does the energy come from to make a proton gradient? Let's think fast. Stream of consciousness:
The relevant information is: The proton gradient can be generated through either noncyclic or cyclic photophosphorylation. So the final answer is either noncyclic or cyclic photophosphorylation.